Surgical instrument with contained dual helix actuator assembly

ABSTRACT

An apparatus comprises an end effector, an elongate shaft, and a handle assembly. The shaft includes an articulation section that is operable to deflect the end effector away from the longitudinal axis of the shaft. The handle assembly includes a rotary member positioned within an intermediate section of the handle assembly. The rotary member is rotatable about an axis that is parallel to the longitudinal axis of the shaft. The rotary member is operable to control the articulation section of the shaft. The rotary member may include opposing thread sections that simultaneously drive lead screws in opposite longitudinal directions, to thereby control the articulation section. The shaft may be rotatable relative to the handle assembly, and the apparatus may selectively lock or resist such rotation based on the articulation state of the articulation section.

PRIORITY

This application is a continuation-in-part of U.S. application Ser. No.13/235,623, entitled “Control Features for Articulating SurgicalDevice,” filed Sep. 19, 2011, the disclosure of which is incorporated byreference herein, and which claims priority to U.S. ProvisionalApplication No. 61/386,094, filed Sep. 24, 2010, entitled “ArticulatingSurgical Device,” the disclosure of which is incorporated by referenceherein.

BACKGROUND

A variety of surgical instruments include a tissue cutting element andone or more elements that transmit RF energy to tissue (e.g., tocoagulate or seal the tissue). An example of such a device is theENSEAL® Tissue Sealing Device by Ethicon Endo-Surgery, Inc., ofCincinnati, Ohio. Further examples of such devices and related conceptsare disclosed in U.S. Pat. No. 6,500,176 entitled “ElectrosurgicalSystems and Techniques for Sealing Tissue,” issued Dec. 31, 2002, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.7,112,201 entitled “Electrosurgical Instrument and Method of Use,”issued Sep. 26, 2006, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 7,125,409, entitled “ElectrosurgicalWorking End for Controlled Energy Delivery,” issued Oct. 24, 2006, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.7,169,146 entitled “Electrosurgical Probe and Method of Use,” issuedJan. 30, 2007, the disclosure of which is incorporated by referenceherein; U.S. Pat. No. 7,186,253, entitled “Electrosurgical Jaw Structurefor Controlled Energy Delivery,” issued Mar. 6, 2007, the disclosure ofwhich is incorporated by reference herein; U.S. Pat. No. 7,189,233,entitled “Electrosurgical Instrument,” issued Mar. 13, 2007, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.7,220,951, entitled “Surgical Sealing Surfaces and Methods of Use,”issued May 22, 2007, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 7,309,849, entitled “PolymerCompositions Exhibiting a PTC Property and Methods of Fabrication,”issued Dec. 18, 2007, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 7,311,709, entitled “ElectrosurgicalInstrument and Method of Use,” issued Dec. 25, 2007, the disclosure ofwhich is incorporated by reference herein; U.S. Pat. No. 7,354,440,entitled “Electrosurgical Instrument and Method of Use,” issued Apr. 8,2008, the disclosure of which is incorporated by reference herein; U.S.Pat. No. 7,381,209, entitled “Electrosurgical Instrument,” issued Jun.3, 2008, the disclosure of which is incorporated by reference herein;U.S. Pub. No. 2011/0087218, entitled “Surgical Instrument ComprisingFirst and Second Drive Systems Actuatable by a Common TriggerMechanism,” published Apr. 14, 2011, the disclosure of which isincorporated by reference herein; and U.S. Pub. No. 2012/0116379,entitled “Motor Driven Electrosurgical Device with Mechanical andElectrical Feedback,” published May 10, 2012, the disclosure of which isincorporated by reference herein.

In addition, a variety of surgical instruments include a shaft having anarticulation section, providing enhanced positioning capabilities for anend effector that is located distal to the articulation section of theshaft. Examples of such devices include various models of the ENDOPATH®endocutters by Ethicon Endo-Surgery, Inc., of Cincinnati, Ohio. Furtherexamples of such devices and related concepts are disclosed in U.S. Pat.No. 7,380,696, entitled “Articulating Surgical Stapling InstrumentIncorporating a Two-Piece E-Beam Firing Mechanism,” issued Jun. 3, 2008,the disclosure of which is incorporated by reference herein; U.S. Pat.No. 7,404,508, entitled “Surgical Stapling and Cutting Device,” issuedJul. 29, 2008, the disclosure of which is incorporated by referenceherein; U.S. Pat. No. 7,455,208, entitled “Surgical Instrument withArticulating Shaft with Rigid Firing Bar Supports,” issued Nov. 25,2008, the disclosure of which is incorporated by reference herein; U.S.Pat. No. 7,506,790, entitled “Surgical Instrument Incorporating anElectrically Actuated Articulation Mechanism,” issued Mar. 24, 2009, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.7,549,564, entitled “Surgical Stapling Instrument with an ArticulatingEnd Effector,” issued Jun. 23, 2009, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 7,559,450, entitled“Surgical Instrument Incorporating a Fluid Transfer ControlledArticulation Mechanism,” issued Jul. 14, 2009, the disclosure of whichis incorporated by reference herein; U.S. Pat. No. 7,654,431, entitled“Surgical Instrument with Guided Laterally Moving Articulation Member,”issued Feb. 2, 2010, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 7,780,054, entitled “Surgical Instrumentwith Laterally Moved Shaft Actuator Coupled to Pivoting ArticulationJoint,” issued Aug. 24, 2010, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 7,784,662, entitled “Surgical Instrumentwith Articulating Shaft with Single Pivot Closure and Double Pivot FrameGround,” issued Aug. 31, 2010, the disclosure of which is incorporatedby reference herein; and U.S. Pat. No. 7,798,386, entitled “SurgicalInstrument Articulation Joint Cover,” issued Sep. 21, 2010, thedisclosure of which is incorporated by reference herein.

While several medical devices have been made and used, it is believedthat no one prior to the inventors has made or used the inventiondescribed in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims which particularly pointout and distinctly claim this technology, it is believed this technologywill be better understood from the following description of certainexamples taken in conjunction with the accompanying drawings, in whichlike reference numerals identify the same elements and in which:

FIG. 1 depicts a side elevational view of an exemplary electrosurgicalmedical device;

FIG. 2 depicts a perspective view of the end effector of the device ofFIG. 1, in an open configuration;

FIG. 3 depicts another perspective view of the end effector of thedevice of FIG. 1, in an open configuration;

FIG. 4 depicts a cross-sectional end view of the end effector of FIG. 2,in a closed configuration and with the blade in a distal position;

FIG. 5 depicts a perspective view of another exemplary electrosurgicalmedical device, with an articulation control knob;

FIG. 6 depicts a cross-sectional end view of a shaft assembly of thedevice of FIG. 5, taken along line 6-6 of FIG. 5;

FIG. 7 depicts a perspective view of components of the shaft assemblyand end effector of the device of FIG. 5;

FIG. 8 depicts a perspective view of a support member of the shaftassembly of the device of FIG. 5;

FIG. 9 depicts a partial perspective view of articulation controlcomponents of the device of FIG. 5, along one side of the supportmember;

FIG. 10 depicts a partial perspective view of articulation controlcomponents of the device of FIG. 5, along another side of the supportmember;

FIG. 11 depicts a top plan view of the articulation control componentsof FIGS. 9-10;

FIG. 12 depicts a partial perspective view of the articulation controlcomponents of FIG. 9 surrounded by a sheath;

FIG. 13 depicts a side elevational view of the handle assembly of thedevice of FIG. 5, with a housing half removed;

FIG. 14 depicts a side elevational view of articulation controlcomponents of the handle assembly of FIG. 13, with half of anarticulation control knob body removed;

FIG. 15 depicts a perspective view of articulation control components ofthe handle assembly of FIG. 13, coupled with the articulation controlcomponents of FIGS. 9-10;

FIG. 16 depicts a side cross-sectional view of the articulation controlcomponents of FIG. 15, taken along line 16-16 of FIGS. 15;

FIG. 17A depicts a partial cross-sectional view of articulation controlcomponents and the articulation section of the shaft of the device ofFIG. 5, with the articulation section in a substantially straightconfiguration;

FIG. 17B depicts a partial cross-sectional view of the components ofFIG. 17A, with the articulation section in a first stage ofarticulation;

FIG. 17C depicts a partial cross-sectional view of the components ofFIG. 17A, with the articulation section in a second stage ofarticulation;

FIG. 18 depicts a side elevational view of the handle assembly of anexemplary alternative electrosurgical medical device with anarticulation control knob;

FIG. 19 depicts a side elevational view of articulation controlcomponents of the handle assembly of FIG. 18, with half of anarticulation control knob body removed;

FIG. 20 depicts a side cross-sectional view of articulation controlcomponents of the handle assembly of FIG. 18;

FIG. 21 depicts a perspective view of articulation control components ofthe handle assembly of FIG. 18;

FIG. 22 depicts a top cross-sectional view of the articulation controlcomponents of FIG. 21, taken along line 22-22 of FIG. 21;

FIG. 23 depicts an exploded perspective view of some of the articulationcontrol components of the handle assembly of FIG. 18;

FIG. 24 depicts another exploded perspective view of some of thearticulation control components of the handle assembly of FIG. 18;

FIG. 25 depicts a cross-sectional end view of a detent feature of thearticulation control components of the handle assembly of FIG. 18, takenalong line 25-25 of FIG. 18;

FIG. 26 depicts a perspective view of an exemplary alternative rivetmember that may be used in the articulation control components of ahandle assembly;

FIG. 27 depicts a top cross-sectional view of articulation controlcomponents including the rivet member of FIG. 26;

FIG. 28 depicts a partial side view distal portion of an exemplaryalternative handle assembly, with a housing half and other componentsremoved to reveal an exemplary friction ring;

FIG. 29 depicts a partial perspective view of exemplary articulationbraking features that may be used in the articulation control componentsof a handle assembly;

FIG. 30A depicts an end view of the articulation braking features ofFIG. 29, with the knob at a home position where the articulation sectionof the shaft is substantially straight; and

FIG. 30B depicts an end view of the articulation braking features ofFIG. 20, with the knob at a rotated position where the articulationsection of the shaft is substantially articulated.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the technology may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presenttechnology, and together with the description serve to explain theprinciples of the technology; it being understood, however, that thistechnology is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the technology shouldnot be used to limit its scope. Other examples, features, aspects,embodiments, and advantages of the technology will become apparent tothose skilled in the art from the following description, which is by wayof illustration, one of the best modes contemplated for carrying out thetechnology. As will be realized, the technology described herein iscapable of other different and obvious aspects, all without departingfrom the technology. Accordingly, the drawings and descriptions shouldbe regarded as illustrative in nature and not restrictive.

It is further understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Thefollowing-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims.

I. Exemplary Electrosurgical Device with Articulation Feature

FIGS. 1-4 show an exemplary electrosurgical instrument (10) that isconstructed and operable in accordance with at least some of theteachings of U.S. Pat. No. 6,500,176; U.S. Pat. No. 7,112,201; U.S. Pat.No. 7,125,409; U.S. Pat. No. 7,169,146; U.S. Pat. No. 7,186,253; U.S.Pat. No. 7,189,233; U.S. Pat. No. 7,220,951; U.S. Pat. No. 7,309,849;U.S. Pat. No. 7,311,709; U.S. Pat. No. 7,354,440; U.S. Pat. No.7,381,209; U.S. Pub. No. 2011/0087218; and/or U.S. Pub. No.2012/0116379. As described therein and as will be described in greaterdetail below, electrosurgical instrument (10) is operable to cut tissueand seal or weld tissue (e.g., a blood vessel, etc.) substantiallysimultaneously. In other words, electrosurgical instrument (10) operatessimilar to an endocutter type of stapler, except that electrosurgicalinstrument (10) provides tissue welding through application of bipolarRF energy instead of providing lines of staples to join tissue. Itshould also be understood that electrosurgical instrument (10) may havevarious structural and functional similarities with the ENSEAL® TissueSealing Device by Ethicon Endo-Surgery, Inc., of Cincinnati, Ohio.Furthermore, electrosurgical instrument (10) may have various structuraland functional similarities with the devices taught in any of the otherreferences that are cited and incorporated by reference herein. To theextent that there is some degree of overlap between the teachings of thereferences cited herein, the ENSEAL® Tissue Sealing Device by EthiconEndo-Surgery, Inc., of Cincinnati, Ohio, and the following teachingsrelating to electrosurgical instrument (10), there is no intent for anyof the description herein to be presumed as admitted prior art. Severalteachings below will in fact go beyond the scope of the teachings of thereferences cited herein and the ENSEAL® Tissue Sealing Device by EthiconEndo-Surgery, Inc., of Cincinnati, Ohio.

A. Exemplary Handpiece and Shaft

Electrosurgical instrument (10) of the present example includes ahandpiece (20), a shaft (30) extending distally from handpiece (20), andan end effector (40) disposed at a distal end of shaft (30). Handpiece(20) of the present example includes a pistol grip (22), a pivotingtrigger (24), an activation button (26), and an articulation control(28). Trigger (24) is pivotable toward and away from pistol grip (22) toselectively actuate end effector (40) as will be described in greaterdetail below. Activation button (26) is operable to selectively activateRF circuitry that is in communication with end effector (40), as willalso be described in greater detail below. In some versions, activationbutton (26) also serves as a mechanical lockout against trigger (24),such that trigger (24) cannot be fully actuated unless button (26) isbeing pressed simultaneously. Examples of how such a lockout may beprovided are disclosed in one or more of the references cited herein. Itshould be understood that pistol grip (22), trigger (24), and button(26) may be modified, substituted, supplemented, etc. in any suitableway, and that the descriptions of such components herein are merelyillustrative. Articulation control (28) of the present example isoperable to selectively control articulation section (36) of shaft (30),which will be described in greater detail below. Various examples offorms that articulation control (28) may take will also be described ingreater detail below, while further examples will be apparent to thoseof ordinary skill in the art in view of the teachings herein.

Shaft (30) of the present example includes an outer sheath (32) and anarticulation section (36). Articulation section (36) is operable toselectively position end effector (40) at various angles relative to thelongitudinal axis defined by sheath (32). Various examples of forms thatarticulation section (36) and other components of shaft (30) may takewill be described in greater detail below, while further examples willbe apparent to those of ordinary skill in the art in view of theteachings herein. For instance, it should be understood that variouscomponents that are operable to actuate articulation section (36) mayextend through the interior of sheath (32). In some versions, shaft (30)is also rotatable about the longitudinal axis defined by sheath (32),relative to handpiece (20), via a knob (34). Such rotation may providerotation of end effector (40) and shaft (30) unitarily. In some otherversions, knob (34) is operable to rotate end effector (40) withoutrotating any portion of shaft (30) that is proximal of articulationsection (36). As another merely illustrative example, electrosurgicalinstrument (10) may include one rotation control that providesrotatability of shaft (30) and end effector (40) as a single unit; andanother rotation control that provides rotatability of end effector (40)without rotating any portion of shaft (30) that is proximal ofarticulation section (36). Other suitable rotation schemes will beapparent to those of ordinary skill in the art in view of the teachingsherein. Of course, rotatable features may simply be omitted if desired.

B. Exemplary End Effector

End effector (40) of the present example comprises a first jaw (42) anda second jaw (44). In the present example, second jaw (44) issubstantially fixed relative to shaft (30); while first jaw (42) pivotsrelative to shaft (30), toward and away from second jaw (42). In someversions, actuators such as rods or cables, etc., may extend throughsheath (32) and be joined with first jaw (42) at a pivotal coupling(43), such that longitudinal movement of the actuator rods/cables/etc.through shaft (30) provides pivoting of first jaw (42) relative to shaft(30) and relative to second jaw (44). Of course, jaws (42, 44) mayinstead have any other suitable kind of movement and may be actuated inany other suitable fashion. By way of example only, and as will bedescribed in greater detail below, jaws (42, 44) may be actuated andthus closed by longitudinal translation of a firing beam (60), such thatactuator rods/cables/etc. may simply be eliminated in some versions.

As best seen in FIGS. 2-4, first jaw (42) defines a longitudinallyextending elongate slot (46); while second jaw (44) also defines alongitudinally extending elongate slot (48). In addition, the top sideof first jaw (42) presents a first electrode surface (50); while theunderside of second jaw (44) presents a second electrode surface (52).Electrode surfaces (50, 52) are in communication with an electricalsource (80) via one or more conductors (not shown) that extend along thelength of shaft (30). Electrical source (80) is operable to deliver RFenergy to first electrode surface (50) at a first polarity and to secondelectrode surface (52) at a second (opposite) polarity, such that RFcurrent flows between electrode surfaces (50, 52) and thereby throughtissue captured between jaws (42, 44). In some versions, firing beam(60) serves as an electrical conductor that cooperates with electrodesurfaces (50, 52) (e.g., as a ground return) for delivery of bipolar RFenergy captured between jaws (42, 44). Electrical source (80) may beexternal to electrosurgical instrument (10) or may be integral withelectrosurgical instrument (10) (e.g., in handpiece (20), etc.), asdescribed in one or more references cited herein or otherwise. Acontroller (82) regulates delivery of power from electrical source (80)to electrode surfaces (50, 52). Controller (82) may also be external toelectrosurgical instrument (10) or may be integral with electrosurgicalinstrument (10) (e.g., in handpiece (20), etc.), as described in one ormore references cited herein or otherwise. It should also be understoodthat electrode surfaces (50, 52) may be provided in a variety ofalternative locations, configurations, and relationships.

As best seen in FIG. 4, the lower side of first jaw (42) includes alongitudinally extending recess (58) adjacent to slot (46); while theupper side of second jaw (44) includes a longitudinally extending recess(58) adjacent to slot (48). FIG. 2 shows the upper side of first jaw(42) including a plurality of teeth serrations (46). It should beunderstood that the lower side of second jaw (44) may includecomplementary serrations that nest with serrations (46), to enhancegripping of tissue captured between jaws (42, 44) without necessarilytearing the tissue. FIG. 3 shows an example of serrations (46) in firstjaw (42) as mainly recesses; with serrations (48) in second jaw (44) asmainly protrusions. Of course, serrations (46, 48) may take any othersuitable form or may be simply omitted altogether. It should also beunderstood that serrations (46, 48) may be formed of an electricallynon-conductive, or insulative, material, such as plastic, glass, and/orceramic, for example, and may include a treatment such aspolytetrafluoroethylene, a lubricant, or some other treatment tosubstantially prevent tissue from getting stuck to jaws (42, 44).

With jaws (42, 44) in a closed position, shaft (30) and end effector(40) are sized and configured to fit through trocars having variousinner diameters, such that electrosurgical instrument (10) is usable inminimally invasive surgery, though of course electrosurgical instrument(10) could also be used in open procedures if desired. By way of exampleonly, with jaws (42, 44) in a closed position, shaft (30) and endeffector (40) may present an outer diameter of approximately 5 mm.Alternatively, shaft (30) and end effector (40) may present any othersuitable outer diameter (e.g., between approximately 2 mm andapproximately 20 mm, etc.).

As another merely illustrative variation, either jaw (42, 44) or both ofjaws (42, 44) may include at least one port, passageway, conduit, and/orother feature that is operable to draw steam, smoke, and/or othergases/vapors/etc. from the surgical site. Such a feature may be incommunication with a source of suction, such as an external source or asource within handpiece (20), etc. In addition, end effector (40) mayinclude one or more tissue cooling features (not shown) that reduce thedegree or extent of thermal spread caused by end effector (40) onadjacent tissue when electrode surfaces (50, 52) are activated. Varioussuitable forms that such cooling features may take will be apparent tothose of ordinary skill in the art in view of the teachings herein.

In some versions, end effector (40) includes one or more sensors (notshown) that are configured to sense a variety of parameters at endeffector (40), including but not limited to temperature of adjacenttissue, electrical resistance or impedance of adjacent tissue, voltageacross adjacent tissue, forces exerted on jaws (42, 44) by adjacenttissue, etc. By way of example only, end effector (40) may include oneor more positive temperature coefficient (PTC) thermistor bodies (54,56) (e.g., PTC polymer, etc.), located adjacent to electrodes (50, 52)and/or elsewhere. Data from sensors may be communicated to controller(82). Controller (82) may process such data in a variety of ways. By wayof example only, controller (82) may modulate or otherwise change the RFenergy being delivered to electrode surfaces (50, 52), based at least inpart on data acquired from one or more sensors at end effector (40). Inaddition or in the alternative, controller (82) may alert the user toone or more conditions via an audio and/or visual feedback device (e.g.,speaker, lights, display screen, etc.), based at least in part on dataacquired from one or more sensors at end effector (40). It should alsobe understood that some kinds of sensors need not necessarily be incommunication with controller (82), and may simply provide a purelylocalized effect at end effector (40). For instance, a PTC thermistorbodies (54, 56) at end effector (40) may automatically reduce the energydelivery at electrode surfaces (50, 52) as the temperature of the tissueand/or end effector (40) increases, thereby reducing the likelihood ofoverheating. In some such versions, a PTC thermistor element is inseries with power source (80) and electrode surface (50, 52); and thePTC thermistor provides an increased impedance (reducing flow ofcurrent) in response to temperatures exceeding a threshold. Furthermore,it should be understood that electrode surfaces (50, 52) may be used assensors (e.g., to sense tissue impedance, etc.). Various kinds ofsensors that may be incorporated into electrosurgical instrument (10)will be apparent to those of ordinary skill in the art in view of theteachings herein. Similarly various things that can be done with datafrom sensors, by controller (82) or otherwise, will be apparent to thoseof ordinary skill in the art in view of the teachings herein. Othersuitable variations for end effector (40) will also be apparent to thoseof ordinary skill in the art in view of the teachings herein.

C. Exemplary Firing Beam

As also seen in FIGS. 2-4, electrosurgical instrument (10) of thepresent example includes a firing beam (60) that is longitudinallymovable along part of the length of end effector (40). Firing beam (60)is coaxially positioned within shaft (30), extends along the length ofshaft (30), and translates longitudinally within shaft (30) (includingarticulation section (36) in the present example), though it should beunderstood that firing beam (60) and shaft (30) may have any othersuitable relationship. Firing beam (60) includes a sharp distal blade(64), an upper flange (62), and a lower flange (66). As best seen inFIG. 4, distal blade (64) extends through slots (46, 48) of jaws (42,44), with upper flange (62) being located above jaw (44) in recess (59)and lower flange (66) being located below jaw (42) in recess (58). Theconfiguration of distal blade (64) and flanges (62, 66) provides an“I-beam” type of cross section at the distal end of firing beam (60).While flanges (62, 66) extend longitudinally only along a small portionof the length of firing beam (60) in the present example, it should beunderstood that flanges (62, 66) may extend longitudinally along anysuitable length of firing beam (60). In addition, while flanges (62, 66)are positioned along the exterior of jaws (42, 44), flanges (62, 66) mayalternatively be disposed in corresponding slots formed within jaws (42,44). For instance, each jaw (42, 44) may define a “T”-shaped slot, withparts of distal blade (64) being disposed in one vertical portion ofeach “T”-shaped slot and with flanges (62, 66) being disposed in thehorizontal portions of the “T”-shaped slots. Various other suitableconfigurations and relationships will be apparent to those of ordinaryskill in the art in view of the teachings herein.

Distal blade (64) is substantially sharp, such that distal blade (64)will readily sever tissue that is captured between jaws (42, 44). Distalblade (64) is also electrically grounded in the present example,providing a return path for RF energy as described elsewhere herein. Insome other versions, distal blade (64) serves as an active electrode. Inaddition or in the alternative, distal blade (64) may be selectivelyenergized with ultrasonic energy (e.g., harmonic vibrations atapproximately 55.5 kHz, etc.).

The “I-beam” type of configuration of firing beam (60) provides closureof jaws (42, 44) as firing beam (60) is advanced distally. Inparticular, flange (62) urges jaw (44) pivotally toward jaw (42) asfiring beam (60) is advanced from a proximal position (FIGS. 1-3) to adistal position (FIG. 4), by bearing against recess (59) formed in jaw(44). This closing effect on jaws (42, 44) by firing beam (60) may occurbefore distal blade (64) reaches tissue captured between jaws (42, 44).Such staging of encounters by firing beam (60) may reduce the forcerequired to squeeze grip (24) to actuate firing beam (60) through a fullfiring stroke. In other words, in some such versions, firing beam (60)may have already overcome an initial resistance required tosubstantially close jaws (42, 44) on tissue before encounteringresistance from severing the tissue captured between jaws (42, 44). Ofcourse, any other suitable staging may be provided.

In the present example, flange (62) is configured to cam against a rampfeature at the proximal end of jaw (44) to open jaw (42) when firingbeam (60) is retracted to a proximal position and to hold jaw (42) openwhen firing beam (60) remains at the proximal position. This cammingcapability may facilitate use of end effector (40) to separate layers oftissue, to perform blunt dissections, etc., by forcing jaws (42, 44)apart from a closed position. In some other versions, jaws (42, 44) areresiliently biased to an open position by a spring or other type ofresilient feature. While jaws (42, 44) close or open as firing beam (60)is translated in the present example, it should be understood that otherversions may provide independent movement of jaws (42, 44) and firingbeam (60). By way of example only, one or more cables, rods, beams, orother features may extend through shaft (30) to selectively actuate jaws(42, 44) independently of firing beam (60). Such jaw (42, 44) actuationfeatures may be separately controlled by a dedicated feature ofhandpiece (20). Alternatively, such jaw actuation features may becontrolled by trigger (24) in addition to having trigger (24) controlfiring beam (60). It should also be understood that firing beam (60) maybe resiliently biased to a proximal position, such that firing beam (60)retracts proximally when a user relaxes their grip on trigger (24).

D. Exemplary Operation

In an exemplary use, end effector (40) is inserted into a patient via atrocar. Articulation section (36) is substantially straight when endeffector (40) and part of shaft (30) are inserted through the trocar.Articulation control (28) may then be manipulated to pivot or flexarticulation section (36) of shaft (30) in order to position endeffector (40) at a desired position and orientation relative to ananatomical structure within the patient. Two layers of tissue of theanatomical structure are then captured between jaws (42, 44) bysqueezing trigger (24) toward pistol grip (22). Such layers of tissuemay be part of the same natural lumen defining anatomical structure(e.g., blood vessel, portion of gastrointestinal tract, portion ofreproductive system, etc.) in a patient. For instance, one tissue layermay comprise the top portion of a blood vessel while the other tissuelayer may comprise the bottom portion of the blood vessel, along thesame region of length of the blood vessel (e.g., such that the fluidpath through the blood vessel before use of electrosurgical instrument(10) is perpendicular to the longitudinal axis defined by end effector(40), etc.). In other words, the lengths of jaws (42, 44) may beoriented perpendicular to (or at least generally transverse to) thelength of the blood vessel. As noted above, flanges (62, 66) camminglyact to pivot jaw (44) toward jaw (44) when firing beam (60) is actuateddistally by squeezing trigger (24) toward pistol grip (22).

With tissue layers captured between jaws (42, 44) firing beam (60)continues to advance distally by the user squeezing trigger (24) towardpistol grip (22). As firing beam (60) advances distally, distal blade(64) simultaneously severs the clamped tissue layers, resulting inseparated upper layer portions being apposed with respective separatedlower layer portions. In some versions, this results in a blood vesselbeing cut in a direction that is generally transverse to the length ofthe blood vessel. It should be understood that the presence of flanges(62, 66) immediately above and below jaws (42, 44), respectively, mayhelp keep jaws (42, 44) in a closed and tightly clamping position. Inparticular, flanges (62, 66) may help maintain a significantlycompressive force between jaws (42, 44). With severed tissue layerportions being compressed between jaws (42, 44), electrode surfaces (50,52) are activated with bipolar RF energy by the user depressingactivation button (26). In some versions, electrodes (50, 52) areselectively coupled with power source (80) (e.g., by the user depressingbutton (26), etc.) such that electrode surfaces (50, 52) of jaws (42,44) are activated with a common first polarity while firing beam (60) isactivated at a second polarity that is opposite to the first polarity.Thus, a bipolar RF current flows between firing beam (60) and electrodesurfaces (50, 52) of jaws (42, 44), through the compressed regions ofsevered tissue layer portions. In some other versions, electrode surface(50) has one polarity while electrode surface (52) and firing beam (60)both have the other polarity. In either version (among at least someothers), bipolar RF energy delivered by power source (80) ultimatelythermally welds the tissue layer portions on one side of firing beam(60) together and the tissue layer portions on the other side of firingbeam (60) together.

In certain circumstances, the heat generated by activated electrodesurfaces (50, 52) can denature the collagen within the tissue layerportions and, in cooperation with clamping pressure provided by jaws(42, 44), the denatured collagen can form a seal within the tissue layerportions. Thus, the severed ends of the natural lumen defininganatomical structure are hemostatically sealed shut, such that thesevered ends will not leak bodily fluids. In some versions, electrodesurfaces (50, 52) may be activated with bipolar RF energy before firingbeam (60) even begins to translate distally and thus before the tissueis even severed. For instance, such timing may be provided in versionswhere button (26) serves as a mechanical lockout relative to trigger(24) in addition to serving as a switch between power source (80) andelectrode surfaces (50, 52).

While several of the teachings below are described as variations toelectrosurgical instrument (10), it should be understood that variousteachings below may also be incorporated into various other types ofdevices. By way of example only, in addition to being readilyincorporated into electrosurgical instrument (10), various teachingsbelow may be readily incorporated into the devices taught in any of thereferences cited herein, other types of electrosurgical devices,surgical staplers, surgical clip appliers, and tissue graspers, amongvarious other devices. Other suitable devices into which the followingteachings may be incorporated will be apparent to those of ordinaryskill in the art in view of the teachings herein.

II. Exemplary Articulation Joint Configurations

Articulation section (36) of shaft (30) may take a variety of forms. Byway of example only, articulation section (36) may be configured inaccordance with one or more teachings of U.S. Pub. No. 2012/0078247,entitled “Articulation Joint Features for Articulating Surgical Device,”published Mar. 29, 2012, the disclosure of which is incorporated byreference herein. As another merely illustrative example, articulationsection (36) may be configured in accordance with one or more teachingsof U.S. Pub. No. 2012/0078248, entitled “Articulation Joint Features forArticulating Surgical Device,” published Mar. 29, 2012, the disclosureof which is incorporated by reference herein. Furthermore, articulationsection may be configured in accordance with the teachings of at leastone other of the references cited herein. Various other suitable formsthat articulation section (36) may take will be apparent to those ofordinary skill in the art in view of the teachings herein.

III. Exemplary Articulation Control Configurations

As noted above, some versions of handpiece (20) include an articulationcontrol (28), which is operable to control articulation section (36) ofshaft (30) to thereby selectively position end effector (40) at variousangles relative to the longitudinal axis defined by sheath (32). Severalexamples of forms that articulation control (28) and other components ofhandpiece (20) may take will be described in greater detail below, whilefurther examples will be apparent to those of ordinary skill in the artin view of the teachings herein. By way of example only, some merelyillustrative alternative examples of articulation control (28) aredisclosed in U.S. Pub. No. 2012/0078243, entitled “Control Features forArticulating Surgical Device,” published Mar. 29, 2012, the disclosureof which is incorporated by reference herein; and in U.S. Pub. No.2012/0078244, entitled “Control Features for Articulating SurgicalDevice,” published Mar. 29, 2012, the disclosure of which isincorporated by reference herein.

A. Exemplary Articulation Control with Perpendicular Rotary Knob

FIG. 5 depicts an exemplary electrosurgical instrument (100) thatincludes a handpiece (120), a shaft (130) extending distally fromhandpiece (120), and an end effector (140) disposed at a distal end ofshaft (130). Handpiece (120) of the present example includes a pistolgrip (122), a pivoting trigger (124), an activation button (126), and arotary articulation knob (128). Trigger (124) is pivotable toward andaway from pistol grip (122) to selectively actuate end effector (140) asdescribed above and as described in one or more of the references citedherein. Activation button (126) is operable to selectively activate RFcircuitry that is in communication with end effector (140), as alsodescribed above and as described in one or more reference cited herein.In some versions, activation button (126) also serves as a mechanicallockout against trigger (124), such that trigger (124) cannot be fullyactuated unless button (126) is being pressed simultaneously. Examplesof how such a lockout may be provided are disclosed in one or more ofthe references cited herein. It should be understood that pistol grip(122), trigger (124), and button (126) may be modified, substituted,supplemented, etc. in any suitable way, and that the descriptions ofsuch components herein are merely illustrative. Articulation knob (128)of the present example is operable to selectively control articulationsection (136) of shaft (130), as will be described in greater detailbelow.

Shaft (130) of the present example includes an outer sheath (132), anarticulation section (136) at the distal end of sheath (132), and acutting member driver tube (138) that is slidably and coaxially disposedwithin sheath (132). Cutting member driver tube (138) is secured to adriver block (139), which is further secured to a cutting member (146)of end effector (140). Cutting member driver tube (138) is movablelongitudinally to drive driver block (139) longitudinally, to therebymove cutting member (146) longitudinally. Cutting member (146) isessentially equivalent to firing beam (60) described above. The proximalportion (148) of end effector (140) includes an insert (not shown) thatdefines a channel containing the part of cutting member (146) thatextends through proximal portion (148). This channel is configured topermit cutting member (146) to readily translate relative to the insert,while also preventing cutting member (146) from buckling within theinsert when cutting member (146) encounters a load during distaladvancement of cutting member (146).

In the present example, driver tube (138) is advanced distally bysqueezing trigger (124) toward pistol grip (122); while driver tube(138) is retracted proximally by releasing trigger (124) and/or byactively moving trigger (124) away from pistol grip (122). As shown inFIG. 13, a yoke (125) couples trigger (124) with driver tube (138). Ofcourse, cutting member (146) may be moved in any other suitable fashion.Articulation section (136) of the present example is operable toselectively position end effector (140) at various angles relative tothe longitudinal axis defined by sheath (132). Various examples of formsthat articulation section (136) and other components of shaft (130) maytake are described in various references cited herein, while furtherexamples will be apparent to those of ordinary skill in the art in viewof the teachings herein. Similarly, end effector (140) may be configuredin accordance with end effector (40) described above, in accordance withthe teachings of various references cited herein, and/or in any othersuitable way as will be apparent to those of ordinary skill in the artin view of the teachings herein.

In some versions, shaft (130) is also rotatable about the longitudinalaxis defined by sheath (132), relative to handpiece (120), via a knob(134). Such rotation may provide rotation of end effector (140) andshaft (130) unitarily. In some other versions, knob (134) is operable torotate end effector (140) without rotating any portion of shaft (130)that is proximal of articulation section (136). As another merelyillustrative example, electrosurgical instrument (100) may include onerotation control that provides rotatability of shaft (130) and endeffector (140) as a single unit; and another rotation control thatprovides rotatability of end effector (140) without rotating any portionof shaft (130) that is proximal of section (136). Other suitablerotation schemes will be apparent to those of ordinary skill in the artin view of the teachings herein. Of course, rotatable features maysimply be omitted if desired.

FIGS. 6-12 show various components of shaft (130) that provide controlfor articulation of articulation section (136). In particular, thesecomponents include a separator (150), a first articulation band (160)with an associated drive member (162), and a second articulation band(170) with an associated drive member (172). As best seen in FIG. 6,separator (150) includes an upper lumen (151), a middle lumen (152), anda lower lumen (153). Separator (150) also includes side recesses (154),a distal projection (156), and a gap (158). Separator (150) is disposedwithin cutting member driver tube (138) and maintains a fixedlongitudinal position during operation of instrument (100). Thus,separator (150) and outer sheath (132) remain stationary relative toeach other and relative to handpiece (120); while cutting member drivertube (138) reciprocates relative to separator (150), outer sheath (132),and handpiece (120). Distal projection (156) is configured to permittranslation of driver block (139) substantially free from interferenceby distal projection (156) or by any other portion of separator (150).

In the present example, separator (150) is formed as two pieces arrangedin an end-to-end configuration, with a distal projection from theproximal piece helping to define gap (158). Of course, separator (150)may alternatively be formed as a single piece or any other suitablenumber of pieces. By way of example only, gap (158) may be formed as acutout from a single piece of material.

As will be described in greater detail below, a wire (900) extendsthrough separator (150) to provide electrical communication to endeffector (140). In particular, wire (900) extends through middle lumen(152) from the proximal end of separator (150) until wire (900) reachesgap (158). At gap (158), wire (900) transitions down to lower lumen(153), and extends through lower lumen (153) until reaching the distalend of separator (150). Wire (900) then extends across articulationsection (136) to end effector (140). Wire (900) is thus operable tocommunicate power from a power source to end effector (140) inaccordance with the teachings herein and in accordance with theteachings of various references cited herein. Distal projection (156)protects wire (900) from driver block (139), such that driver block(139) is unable to contact wire (900) regardless of the longitudinalposition of driver block (139) along distal projection (156).

First articulation band (160) is slidably disposed in one side recess(154) of separator (150) while second articulation band (170) isslidably disposed in the other side recess (154) of separator (150).Referring back to FIG. 6, side recesses (154) include longitudinallyextending grooves (155) that are configured to reduce the contactsurface area with articulation bands (160, 170), thereby reducingfriction between separator (150) and articulation bands (160, 170).Separator (150) may also be formed of a low friction material and/orinclude a surface treatment to reduce friction. Articulation bands (160,170) both extend longitudinally along the entire length of shaft (130),including through articulation section (136). As shown in FIG. 7, thedistal end (166) of first articulation band (160) is secured to one sideof the proximal portion (148) of end effector (140) at an anchor point.The distal end (176) of second articulation band (170) is secured to theother side of proximal portion (148) of end effector (140) at an anchorpoint. As will be described in greater detail below, rotary articulationknob (128) is operable to selectively advance one articulation band(160, 170) distally while simultaneously retracting the otherarticulation band (160, 170) proximally, and vice-versa. It should beunderstood that this opposing translation will cause articulationsection (136) to bend, thereby articulating end effector (140). Inparticular, end effector (140) will deflect toward whicheverarticulation band (160, 170) is being retracted proximally; and awayfrom whichever articulation band (160, 170) is being advanced distally.

As best seen in FIG. 9, drive member (162) is unitarily secured toarticulation band (160) and includes a notch (164) extending laterallyinwardly. As best seen in FIG. 10, drive member (172) is unitarilysecured to articulation band (170) and includes a notch (174) extendinglaterally inwardly. As best seen in FIG. 11, drive members (162, 164)are spaced and configured such that notches (164, 174) are at differentlongitudinal positions along the length of separator (150). As best seenin FIG. 12, the proximal portion of cutting member driver tube (138)includes longitudinally extending slots (137). Drive members (162, 172)are slidably disposed in slots (137) and notches (164, 174) are radiallypositioned outside the outer circumference of cutting member driver tube(138). Slots (137) are configured to enable free translation of cuttingmember driver tube (138) relative to drive members (162, 172), to thusenable free actuation of cutting member (164) regardless of thearticulation state of articulation section (136). In other words, slots(137) are configured to enable free translation of drive members (162,172) relative to cutting member driver tube (138), to thus enable freearticulation of articulation section (136) regardless of thelongitudinal position of cutting member (164).

As shown in FIGS. 13-14, rotary articulation knob (128) is coaxiallypositioned about the proximal portion of driver tube (138) andencompasses drive members (162, 172). Articulation knob (128) isoriented perpendicular to the longitudinal axis defined by shaft (130)and is rotatable about the longitudinal axis defined by shaft (130). Aswill be described in greater detail below, such rotation of articulationknob (128) will cause opposing translation of drive members (162, 172),with the directions of such opposing translations depending on thedirection in which articulation knob (128) is rotated, such thatrotation of articulation knob (128) will articulate end effector (140).As shown in FIGS. 14, articulation knob (128) includes a first internalthreading (180) and a second internal threading (182). Threadings (181,182) have opposing pitch angles or orientations in this example.

As best seen in FIGS. 14-15, a first lead screw (183) and a second leadscrew (184) are slidably disposed along a pair of pins (123), which aresecured to housing (121). Thus, lead screws (183, 184) are operable totranslate within housing (121) but are prevented from rotating withinhousing (121). First lead screw (183) includes exterior threading (185)that is engaged with threading (181) of articulation knob (128); whilesecond lead screw (184) includes exterior threading (186) that isengaged with threading (182) of articulation knob (128). The pitch angleof threading (185) complements the pitch angle of threading (181); whilethe pitch angle of threading (186) complements the pitch angle ofthreading (182). It should therefore be understood that, due to theopposing pitch angles, rotation of knob (128) in a first direction willdrive lead screw (183) distally while simultaneously driving lead screw(184) proximally; and rotation of knob in a second direction will drivelead screw (183) proximally while simultaneously driving lead screw(184) distally.

The angles of threading (181, 182, 185, 186) are also configured suchthat articulation section (136) will be effectively locked in any givenarticulated position, such that transverse loads on end effector (140)will generally not bend articulation section (136), due to frictionbetween threading (181, 182, 185, 186). In other words, articulationsection (136) will only change its configuration when knob (128) isrotated. While the angles of threading may substantially prevent bendingof articulation section (136) in response to transverse loads on endeffector (140), the angles may still provide ready rotation ofarticulation knob (128) to translate lead screws (183, 184). By way ofexample only, the angles of threading (181, 182, 185, 186) may beapproximately +/−2 degrees or approximately +/−3 degrees. Other suitableangles will be apparent to those of ordinary skill in the art in view ofthe teachings herein. It should also be understood that threading (181,182, 185, 186) may have a square or rectangular cross-section or anyother suitable configuration.

As best seen in FIGS. 15-16, a first tensioner gear (191) is threadablyengaged with first lead screw (183); while a second tensioner gear (192)is threadably engaged with second lead screw (184). Thus, thelongitudinal position of first tensioner gear (191) relative to firstlead screw (183) may be adjusted by rotating first tensioner gear (191)relative to first lead screw (183); while the longitudinal position ofsecond tensioner gear (192) relative to second lead screw (184) may beadjusted by rotating second tensioner gear (192) relative to second leadscrew (184). Otherwise, first tensioner gear (191) will translateunitarily with first lead screw (183); while second tensioner gear (192)will translate unitarily with second lead screw (184).

First tensioner gear (191) is also engaged with a washer (193), which isfurther engaged with notch (174) of drive member (172). The engagementbetween washer (193) and drive member (172) is such that washer (193)and drive member (172) will translate together. In some versions, washer(193) is secured to tensioner gear (191) in such a manner that tensionergear (191) both pulls washer (193) distally and pushes washer (193)proximally. Thus, in some such versions, first lead screw (183) isoperable to both push articulation band (170) distally and pullarticulation band (170) proximally, depending on which direction knob(128) is rotated. In the present example, however, tensioner gear (191)merely abuts washer (193), such that tensioner gear (191) is operable topush washer (193) proximally but cannot pull washer (193) distally.Thus, in the present example, first lead screw (183) is operable to pullarticulation band (170) proximally but cannot actively push articulationband (170) distally. Instead, first lead screw (183) may simply pulltensioner gear (191) distally to enable articulation band (170), drivemember (172), and washer (193) to be driven distally in response toproximal retraction of articulation band (160) as communicated througharticulation section (136). Other suitable relationships will beapparent to those of ordinary skill in the art in view of the teachingsherein. It should also be understood that drive member (172) and/orwasher (193) may be rotatable relative to tensioner gear (191), whichmay permit rotation of shaft (130) by knob (134). As described ingreater detail below, tensioner gear (191) may be used to take out anytolerance gaps between drive member (172) and lead screw (183).

Similarly, second tensioner gear (192) is engaged with a washer (194),which is further engaged with notch (164) of drive member (162). Theengagement between washer (194) and drive member (162) is such thatwasher (194) and drive member (162) will translate together. In someversions, washer (194) is secured to tensioner gear (192) in such amanner that tensioner gear (192) both pulls washer (194) distally andpushes washer (194) proximally. Thus, in some such versions, second leadscrew (184) is operable to both push articulation band (160) distallyand pull articulation band (160) proximally, depending on whichdirection knob (128) is rotated. In the present example however,tensioner gear (192) merely abuts washer (194), such that tensioner gear(192) is operable to push washer (194) proximally but cannot pull washer(194) distally. Thus, in the present example, second lead screw (184) isoperable to pull articulation band (160) proximally but cannot activelypush articulation band (160) distally. Instead, second lead screw (184)may simply pull tensioner gear (192) distally to enable articulationband (160), drive member (162), and washer (194) to be driven distallyin response to proximal retraction of articulation band (170) ascommunicated through articulation section (136). Other suitablerelationships will be apparent to those of ordinary skill in the art inview of the teachings herein. It should also be understood that drivemember (162) and/or washer (194) may be rotatable relative to tensionergear (192), which may permit rotation of shaft (130) by knob (134). Asdescribed in greater detail below, tensioner gear (192) may be used totake out any tolerance gaps between drive member (162) and lead screw(184).

FIGS. 17A-17C show several of the above described components interactingto bend articulation section (136) to articulate end effector (140). InFIG. 17A, articulation (136) is in a substantially straightconfiguration. Then, knob (128) is rotated, which causes lead screw(183) to translate proximally and lead screw (184) to advance distally.This proximal translation of lead screw (183) pulls articulation band(170) proximally, which causes articulation section (136) to startbending as shown in FIG. 17B. This bending of articulation section (136)pulls articulation band (160) distally. The distal advancement of leadscrew (184) in response to rotation of knob (128) enables articulationband (160) and drive member (162) to advance distally. In some otherversions, the distal advancement of lead screw (184) actively drivesdrive member (162) and articulation band (160) distally. As the usercontinues rotating knob (128), the above described interactions continuein the same fashion, resulting in further bending of articulationsection (136) as shown in FIG. 17C. It should be understand thatrotating knob (128) in the opposite direction will cause articulationsection (136) to straighten, and further rotation in the oppositedirection will cause articulation section (136) to bend in the oppositedirection.

In some versions, knob (128) includes a visual indicator that isassociated with articulation section (136) being in a substantiallystraight configuration. Such a visual indicator may align with acorresponding visual indicator on housing (121) of handpiece (120).Thus, when a user has rotated knob (128) to make articulation section(136) approach a substantially straight configuration, the user mayobserve such indicators to confirm whether articulation section (136)has in fact reached a substantially straight configuration. By way ofexample only, this may be done right before instrument (100) iswithdrawn from a trocar to reduce the likelihood of articulation section(136) snagging on a distal edge of the trocar. Of course, suchindicators are merely optional.

In some instances, manufacturing inconsistencies may result inarticulation bands (160, 170) having slightly different lengths. Inaddition or in the alternative, there may be inherent manufacturingrelated inconsistencies in the initial positioning of lead screws (183,184) relative to articulation knob (128), inconsistencies in the initialpositioning of tensioner gears (191, 192) relative to lead screws (183,184), and/or other inconsistencies that might result in undesirablepositioning/relationships of articulation bands (160, 170). Suchinconsistencies may result in lost motion or slop in the operation ofthe articulation features of instrument (100). To address such issues,tensioner gears (191, 192) may be rotated relative to lead screws (183,184) to adjust the longitudinal position of drive members (162, 172)relative to lead screws (183, 184). For instance, if there isinsufficient tension in articulation band (170), tensioner gear (191)may be rotated to drive washer (193) and drive member (172) proximallyuntil articulation band (170) reaches a sufficient degree of tension.Similarly, if there is insufficient tension in articulation band (160),tensioner gear (192) may be rotated to drive washer (195) and drivemember (162) proximally until articulation band (160) reaches asufficient degree of tension. Lead screws (183, 184) may remainsubstantially stationary during such adjustments. Articulation section(136) may remain substantially straight during such adjustments and mayeven be held substantially straight during such adjustments.

In some versions, tensioner gears (191, 192) are rotated manually. Insome other versions, tensioner gears (191, 192) are rotatedautomatically by a rack or other gear. In some such automatedcalibration systems, a control logic may monitor the load on a motorthat is being used to drive a calibrating rack or gear that is engagedwith tensioner gear (191, 192), and may automatically stop driving sucha rack or gear when the load reaches a threshold associated with propertensioning of band (160, 170). For instance, in cases wheremanufacturing inconsistencies or tolerance provide an initial gapbetween tensioner gears (191, 192) and washers (193, 194), or betweenwashers (193, 194) and drive members (162, 172), tensioner gears (191,192) may be rotated until such gaps are closed and sufficient contact ismade between previously gapped components. As another merelyillustrative variation, tensioner gears (191, 192) may be automaticallystopped when the proximal ends of bands (160, 170) and/or drive members(162, 172) reach a certain point. Various suitable ways in whichtensioner gears (191, 192) may be adjusted will be apparent to those ofordinary skill in the art in view of the teachings herein. It shouldalso be understood that tensioner gears (191, 192) may be heat staked,glued, welded, or otherwise bonded to the respective lead screws (183,184) when the gaps between drive members (162, 172) and their respectivewashers (193, 194) reach zero. Such bonding may prevent subsequentmovement of tensioner gears (191, 192) relative to their respective leadscrews (183, 184).

As another merely illustrative example, manufacturing inconsistenciesmay be addressed at the distal ends of bands (160, 170). For instance,before the distal ends of bands (160, 170) are secured to the proximalportion (148) of end effector (140), articulation section (136) may beheld in a straight configuration and bands (160, 170) may be pulleddistally to remove any slack in bands (160, 170). With bands (160, 170)both being in tension, bands (160, 170) may then be welded or otherwisesecured to proximal portion (148) of end effector (140). It should beunderstood that this form of calibration is not limited to instrument(100), such that this form of calibration may be readily applied tovarious other instruments described herein, among others. Other suitablestructures and methods for calibration will be apparent to those ofordinary skill in the art in view of the teachings herein.

B. Exemplary Articulation Control with Perpendicular Rotary Knob andContainment Rings

FIG. 18 depicts an exemplary alternative electrosurgical instrument(200) that includes a handpiece (220), a shaft (230) extending distallyfrom handpiece (220), and an end effector (not shown) disposed at adistal end of shaft (230). The end effector of instrument (200) issubstantially identical to end effector (140) of instrument (100)described above. Handpiece (220) of the present example includes apistol grip (222), a pivoting trigger (224), an activation button (226),and a rotary articulation knob (228). Trigger (224) is pivotable towardand away from pistol grip (222) to selectively actuate the end effectoras described above and as described in one or more of the referencescited herein. Activation button (226) is operable to selectivelyactivate RF circuitry that is in communication with the end effector, asalso described above and as described in one or more reference citedherein. In some versions, activation button (226) also serves as amechanical lockout against trigger (224), such that trigger (224) cannotbe fully actuated unless button (226) is being pressed simultaneously.Examples of how such a lockout may be provided are disclosed in one ormore of the references cited herein. It should be understood that pistolgrip (222), trigger (224), and button (226) may be modified,substituted, supplemented, etc. in any suitable way, and that thedescriptions of such components herein are merely illustrative.Articulation knob (228) of the present example is operable toselectively control an articulation section (not shown) of shaft (230),as will be described in greater detail below. The articulation sectionof shaft (230) is substantially identical to articulation section (136)of instrument (100) described above.

Shaft (230) of the present example includes an outer sheath (232), theabove-noted articulation section (not shown) at the distal end of sheath(232), and a cutting member driver tube (238) that is slidably andcoaxially disposed within sheath (232). Cutting member driver tube (238)is secured to a driver block (not shown, but substantially similar todriver block (139) described above), which is further secured to acutting member (not shown, but substantially similar to cutting member(146) described above) of the above-noted end effector. Cutting memberdriver tube (238) is movable longitudinally to drive the driver blocklongitudinally, to thereby move the cutting member longitudinally. Inthe present example, driver tube (238) is advanced distally by squeezingtrigger (224) toward pistol grip (222); while driver tube (238) isretracted proximally by releasing trigger (224) and/or by activelymoving trigger (224) away from pistol grip (222). As shown in FIGS.18-19, a yoke (225) couples trigger (224) with driver tube (238). Ofcourse, the cutting member may be moved in any other suitable fashion.The articulation section of the present example is operable toselectively position the end effector at various angles relative to thelongitudinal axis defined by sheath (232). Various examples of formsthat an articulation section and other components of shaft (230) maytake are described in various references cited herein, while furtherexamples will be apparent to those of ordinary skill in the art in viewof the teachings herein. Similarly, the end effector may be configuredin accordance with end effector (40, 140) described above, in accordancewith the teachings of various references cited herein, and/or in anyother suitable way as will be apparent to those of ordinary skill in theart in view of the teachings herein.

FIGS. 18-24 show various components of shaft (230) that provide controlfor articulation of articulation section (236). In particular, thesecomponents include a separator (250), a first articulation band (260)with an associated drive member (262), and a second articulation band(270) with an associated drive member (272). Separator (250) of thisexample is substantially identical to separator (150) described above.However, one difference between separator (250) of this example andseparator (150) described above is that separator (250) includes aproximal flange (252) that is engaged with housing (221), to preventlongitudinal movement of separator (250) relative to housing (221), asbest seen in FIGS. 19-22. Like separator (150) described above,separator (250) is disposed within cutting member driver tube (238) andmaintains a fixed longitudinal position during operation of instrument(200). Thus, separator (250) and outer sheath (232) remain stationaryrelative to each other and relative to handpiece (220); while cuttingmember driver tube (238) reciprocates relative to separator (250), outersheath (232), and handpiece (220).

First articulation band (260) is slidably disposed in one side recess ofseparator (250) while second articulation band (270) is slidablydisposed in the other side recess of separator (250). Articulation bands(260, 270) both extend longitudinally along the entire length of shaft(230), including through the articulation section. In particular, thedistal end of first articulation band (260) is secured to one side ofthe proximal portion of the end effector at an anchor point. The distalend of second articulation band (270) is secured to the other side ofthe proximal portion of the end effector at an anchor point. As will bedescribed in greater detail below, rotary articulation knob (228) isoperable to selectively advance one articulation band (260, 270)distally while simultaneously retracting the other articulation band(260, 270) proximally, and vice-versa. It should be understood that thisopposing translation will cause the articulation section to bend,thereby articulating the end effector. In particular, the end effectorwill deflect toward whichever articulation band (260, 270) is beingretracted proximally; and away from whichever articulation band (260,270) is being advanced distally.

As best seen in FIG. 22, drive member (262) is unitarily secured toarticulation band (260) and defines a lateral notch (264). Similarly,drive member (272) is unitarily secured to articulation band (270) anddefines a lateral notch (274). Drive members (262, 264) are spaced andconfigured such that notches (264, 274) are at different longitudinalpositions along the length of separator (250). As best seen in FIG.21-22, the proximal portion of cutting member driver tube (238) includeslongitudinally extending slots (237). Drive members (262, 272) areslidably disposed in slots (237) and notches (264, 274) are radiallypositioned outside the outer circumference of cutting member driver tube(238). Slots (237) are configured to enable free translation of cuttingmember driver tube (238) relative to drive members (262, 272), to thusenable free actuation of the cutting member regardless of thearticulation state of the articulation section. In other words, slots(237) are configured to enable free translation of drive members (262,272) relative to cutting member driver tube (238), to thus enable freearticulation of the articulation section regardless of the longitudinalposition of the cutting member.

As shown in FIGS. 18-20, rotary articulation knob (228) is coaxiallypositioned about the proximal portion of driver tube (238) andencompasses drive members (262, 272). Articulation knob (228) is formedby a first knob half (228 a) and a second knob half (228 b).Articulation knob (228) is oriented perpendicular to the longitudinalaxis defined by shaft (230) and is rotatable about the longitudinal axisdefined by shaft (230). As will be described in greater detail below,such rotation of articulation knob (228) will cause opposing translationof drive members (262, 272), with the directions of such opposingtranslations depending on the direction in which articulation knob (228)is rotated, such that rotation of articulation knob (228) willarticulate the end effector.

As best seen in FIG. 23, articulation knob (228) includes a firstinternal threading (280) and a second internal threading (282).Threadings (281, 282) have opposing pitch angles or orientations in thisexample. It should be understood that threading (281) in first knob half(228 a) is continuous with identical threading (281) in second knob half(228 b) when halves (228 a, 228 b) are assembled together to formarticulation knob (228). Likewise, threading (282) in first knob half(228 a) is continuous with identical threading (282) in second knob half(228 b) when halves (228 a, 228 b) are assembled together to formarticulation knob (228). In some versions, an undercut in each sectionof threading (281, 282) is removed in order to facilitate manufacture ofknob halves (228 a, 228 b) using injection molding processes. Of course,knob halves (228 a, 228 b) may be made using any other suitableprocess(es) and/or undercut in threading (281, 282) need not necessarilybe removed.

As best seen in FIGS. 19-21, a first lead screw (283) and a second leadscrew (284) are slidably disposed along a pair of pins (223), which aresecured to housing (221). Lead screws (283, 284) are thus operable totranslate within housing (221) along pins (223); but are prevented fromrotating within housing (221). First lead screw (283) includes exteriorthreading (285) that is engaged with threading (281) of articulationknob (228); while second lead screw (284) includes exterior threading(286) that is engaged with threading (282) of articulation knob (228).The pitch angle of threading (285) complements the pitch angle ofthreading (281); while the pitch angle of threading (286) complementsthe pitch angle of threading (282). It should therefore be understoodthat, due to the opposing pitch angles, rotation of knob (228) in afirst direction will drive lead screw (283) distally whilesimultaneously driving lead screw (284) proximally; and rotation of knobin a second direction will drive lead screw (283) proximally whilesimultaneously driving lead screw (284) distally. Threading (281, 282)may include hard stops at each end of threading (281, 282), to limit thelongitudinal travel of lead screws (283, 284), which may in turn limitthe degree of articulation that may be attained in the articulationsection of shaft (230).

In the present example, the articulation section of shaft (230) is in asubstantially straight configuration when lead screws (283, 284) arelocated at the approximate longitudinal center region of thecorresponding threading (281, 282), such that rotation of knob (282) ina clockwise direction from this “home” position will deflect the endeffector in a first direction away from the longitudinal axis of shaft(230); while rotation of knob (282) in a counterclockwise direction fromthe “home” position will deflect the end effector in a second directionaway from the longitudinal axis of shaft (230). In some other versions,the articulation section of shaft (230) is in a substantially straightconfiguration when lead screws (283, 284) are located at opposite endsof the corresponding threading (281, 282), such that knob (282) willonly rotate in one direction from this “home” position.

The angles of threading (281, 282, 285, 286) may be configured such thatthe articulation section will be effectively locked in any givenarticulated position, such that transverse loads on the end effectorwill generally not bend the articulation section, due to frictionbetween threading (281, 282, 285, 286). In other words, threading (281,282, 285, 286) is configured such that when a load is applied to the endeffector, engagement in between threading (281, 282) and respectivethreading (285, 286) will not slip and cause the articulation state ofthe end effector to change. The articulation control assembly may thusbe self-locking such that the articulation section will only change itsconfiguration when knob (228) is rotated. While the angles of threadingmay substantially prevent bending of the articulation section inresponse to transverse loads on the end effector, the angles may stillprovide ready rotation of articulation knob (228) to translate leadscrews (283, 284). By way of example only, the angles of threading (281,282, 285, 286) may be approximately +/−2 degrees or approximately +/−3degrees. Other suitable angles will be apparent to those of ordinaryskill in the art in view of the teachings herein. It should also beunderstood that threading (281, 282, 285, 286) may have a square orrectangular cross-section or any other suitable configuration.

As best seen in FIG. 22, a first rivet member (291) is engaged withfirst lead screw (283); while a second rivet member (292) is engagedwith second lead screw (284). First rivet member (291) is disposed innotch (274) of drive member (272). The engagement between first rivetmember (291) and drive member (272) is such that first rivet member(291) and drive member (272) will translate together. In other words,first rivet member (291) both pulls drive member (272) proximally andpushes drive member (272) distally, depending on the direction in whichknob (228) is rotated. Thus, first lead screw (283) is operable to bothpush articulation band (270) distally and pull articulation band (270)proximally, depending on which direction knob (228) is rotated, viafirst rivet member (291). Other suitable relationships will be apparentto those of ordinary skill in the art in view of the teachings herein.It should also be understood that drive member (272) and/or first rivetmember (291) may be rotatable relative to first lead screw (283), whichmay permit rotation of shaft (230) by knob (234) as described below.

As noted above, second rivet member (292) is engaged with second leadscrew (284). Second rivet member (292) is disposed in a notch (264) ofdrive member (262). The engagement between second rivet member (292) anddrive member (262) is such that second rivet member (292) and drivemember (262) will translate together. In other words, second rivetmember (292) both pulls drive member (262) proximally and pushes drivemember (262) distally, depending on the direction in which knob (228) isrotated. Thus, second lead screw (284) is operable to both pusharticulation band (260) distally and pull articulation band (260)proximally, depending on which direction knob (228) is rotated. As notedabove, the opposing orientations of threading (285, 286) providesimultaneous opposing translation of rivet members (291, 292) (andsimultaneous opposing translation of lead screws (283, 284)), therebyproviding simultaneous opposing translation of drive members (262, 272).While rivet member (291) pushes distally on the distal end of the notchin drive member (272), rivet member (292) pushes proximally on theproximal end of the notch in drive member (262). Likewise, while rivetmember (292) pushes distally on the distal end of the notch in drivemember (262), rivet member pushes proximally on the proximal end of thenotch in drive member (272). Other suitable relationships will beapparent to those of ordinary skill in the art in view of the teachingsherein. It should also be understood that drive member (262) and/orsecond rivet member (292) may be rotatable relative to second lead screw(284), which may permit rotation of shaft (230) by knob (234) asdescribed below.

As noted above, articulation knob (228) is formed by a first knob half(228 a) and a second knob half (228 b). In some instances, forcesexerted back on knob halves (228 a, 228 b) by lead screws (283, 284) maytend to urge knob halves (228 a, 228 b) to separate from each other,particularly when knob (228) is being rotated to articulate thearticulation section of shaft (230) and tissue and/or friction are/isproviding significant resistance to such articulation. To address thesestresses on knob halves (228 a, 228 b), a pair of containment rings(300, 310) are positioned at each end of assembled knob (228).Containment rings (300, 310) are configured to substantially preventknob halves (228 a, 228 b) from separating from each other.

Containment ring (300) includes a flange (302) and a cylindraceousportion (304). As best seen in FIG. 23, cylindraceous portion (304)include a series of notches (306) angularly arrayed about thecircumference of cylindraceous portion (304). Cylindraceous portion(304) is configured to encompass complementary cylindraceous portions(320 a, 320 b) formed by knob halves (228 a, 228 b). Cylindraceousportions (320 a, 320 b) include axially extending protrusions (322 a,322 b) that are received in notches (306) of cylindraceous portion (304)when knob (228) is assembled with containment ring (300). Thisengagement provides unitary rotation of containment ring (300) with knobhalves (228 a, 228 b).

As best seen in FIGS. 19-20, flange (302) of containment ring (300)engages bosses (227) of housing (221). Bosses (227) restrain containmentring (300) in the radial and axial directions, but permit rotation ofcontainment ring (300) relative to housing (221). In some versions,flange (302) and/or the entire containment ring (300) comprises a lowfriction material to minimize frictional resistance due to contactbetween flange (302) and bosses (227). For instance, flange (302) may beformed of a low friction material or may be coated with a low frictionmaterial. In addition or in the alternative, bosses (227) may comprise alow friction material. In either case, flange (302) and bosses (227) mayprovide a relatively low friction bearing surface as an interfacebetween knob (228) and housing (221). Various suitable materials thatmay be used for flange (302), the entire containment ring (300), and/orbosses (227) will be apparent to those of ordinary skill in the art inview of the teachings herein.

Containment ring (310) is configured similar to containment ring (300).In particular, containment ring (310) includes a flange (312) and acylindraceous portion (314). As best seen in FIG. 23, cylindraceousportion (314) include a series of notches (316) angularly arrayed aboutthe circumference of cylindraceous portion (314). As best seen in FIGS.23-24, assembled knob (228) defines an annular recess (330) thatincludes a plurality of radially extending ribs (332). Annular recess(330) is configured to receive cylindraceous portion (314) ofcontainment ring (310), with ribs (332) being received in notches (316).This engagement provides unitary rotation of containment ring (310) withknob halves (228 a, 228 b).

As best seen in FIGS. 19-20, flange (312) of containment ring (310)engages bosses (229) of housing (221). Bosses (229) restrain containmentring (310) in the radial and axial directions, but permit rotation ofcontainment ring (310) relative to housing (221). In some versions,flange (312) and/or the entire containment ring (310) comprises a lowfriction material to minimize frictional resistance due to contactbetween flange (312) and bosses (229). For instance, flange (312) may beformed of a low friction material or may be coated with a low frictionmaterial. In addition or in the alternative, bosses (229) may comprise alow friction material. In either case, flange (312) and bosses (229) mayprovide a relatively low friction bearing surface as an interfacebetween knob (228) and housing (221). Various suitable materials thatmay be used for flange (312), the entire containment ring (310), and/orbosses (229) will be apparent to those of ordinary skill in the art inview of the teachings herein.

While knob (228) is formed of two halves (228 a, 228 b) in the presentexample, it should be understood that any suitable number of pieces maybe used to form knob, including just one piece or three or more pieces.In versions where three or more pieces are held together, containmentrings (300, 310) may substantially hold such pieces together inaccordance with the teachings above.

In some instances, it may be desirable to provide some form of feedbackto the surgeon to indicate the degree of articulation in thearticulation section of shaft (230). Such feedback may be visual,audible, and/or tactile. A surgeon may wish to receive such feedbackbefore withdrawing shaft (230) from a patient via a trocar, such as toconfirm that the articulation section is in a substantially straightconfiguration before withdrawal. As a merely illustrative example ofvisual feedback, a marking may be provided on the exterior of housing(221) and/or on the exterior of knob (228). For instance, housing (221)and knob (228) may include complementary arrows that align when thearticulation section of shaft (230) is in a straight configuration. Asanother merely illustrative example of visual feedback, the articulationsection of shaft (230) may include a high-contrast line or other visualindicator that may enhance visualization of the degree of articulationof the articulation section. For instance, a high-contrast line may makeit easier to see how straight or bent the articulation section is, sincethe line will bend or straighten in accordance with the articulationstate of the articulation section. Providing a line or other marking onthe articulation section may facilitate viewing of the marking withinthe image provided by an endoscopic camera, such that the surgeon neednot look away from the surgical field presented on a screen coupled withthe endoscopic camera in order to determine the degree of articulationof the articulation section. Other suitable ways of providing visualfeedback to indicate articulation states will be apparent to those ofordinary skill in the art in view of the teachings herein.

Instrument (200) of the present example includes features for providingaudible and tactile feedback relating to the articulation state of thearticulation section of shaft (230). In particular, and as shown inFIGS. 18, 23, and 25, a detent arm (350) is secured to housing (221).Detent arm (350) includes a detent pad (352) that has a protrusion (360)that is configured to snap into a longitudinal recess (340) formed incylindraceous portion (320 a) of knob half (228 a). In the presentexample, recess (340) is only provided in knob half (228 a), and knobhalf (228 b) does not include any similar recess. Detent arm (350) isresiliently biased to urge detent pad (352) radially inwardly towardknob half (228 a). Recess (340) is positioned such that the protrusionof detent pad (352) will snap into recess (340) when the articulationsection of shaft (230) is in a substantially straight configuration.When knob (228) is rotated to articulate the articulation section,detent arm (350) will deform and detent pad (352) will be deflected awayfrom recess (340). In particular, detent arm (350) will effectivelypivot at a bent portion (354) of detent arm (350), which is adjacent tohousing (221).

As best seen in FIG. 25, protrusion (360) includes an upper angledsurface (362) and a lower angled surface (364). Angled surfaces (362,364) are configured to provide a generally smooth transition forprotrusion (360) into and out of recess (340). In some versions, angledsurfaces (362, 364) are substantially symmetric, such that angledsurfaces (362, 364) define complementary angles with detent arm (350).In the present example, however, angled surfaces (362, 364) areasymmetric. In particular, upper surface (362) defines an angle withdetent arm (350) that is greater than the angle defined between lowersurface (364) and detent arm (350). In other words, upper surface (362)is at a more obtuse angle than lower surface (364).

The asymmetry of surfaces (362, 364) in the present example may providea substantially symmetric force profile when knob (228) is initiallyrotated to the left (counterclockwise) or right (clockwise) from thehome position (i.e., from the position where protrusion (360) isdisposed in recess (340)). Conversely, in versions where surfaces (362,364) are symmetric, the forces exerted by cylindraceous portion (320 a)at recess (340) against protrusion (360) may be greater when knob (228)is initially rotated to the left (counterclockwise) than the forcesexerted by cylindraceous portion (320 a) at recess (340) againstprotrusion (360) when knob (228) is initially rotated to the right(clockwise). In other words, symmetric surfaces (362, 364) may in factprovide greater resistance to initial left (counterclockwise) rotationof knob (228) than the resistance provided to initial right (clockwise)rotation of knob (228). This may be due to the fact that forces exertedby cylindraceous portion (320 a) at recess (340) against lower surface(364) are directed substantially away from the pivot provided by bentportion (354) when knob (228) is initially rotated to the right(clockwise), as indicated by arrow (365); whereas the forces exerted bycylindraceous portion (320 a) at recess (340) against upper surface(362) are directed more generally toward the pivot provided by bentportion (354) when knob (228) is initially rotated to the left(counterclockwise), as indicated by arrow (363). Bent portion (354) thusitself provides increased resistance to left (counterclockwise) rotationof knob (228).

Referring back to the present example, orienting upper surface (362) ata more obtuse angle will deflect the forces against surface (362)further away from the pivot provided by bent portion (354) when knob(228) is initially rotated to the left (counterclockwise). In FIG. 25,arrow (365) shows force exerted by cylindraceous portion (320 a) atrecess (340) against lower surface (364) when knob (228) is initiallyrotated to the right (clockwise). Arrow (363) shows force exerted bycylindraceous portion (320 a) at recess (340) against upper surface(362) when knob (228) is initially rotated to the left(counterclockwise). Arrow (363) is directed further away from the pivotprovided by bent portion (354) than it would otherwise be if uppersurface (362) were symmetric with lower surface (364). The more obtusethe angle of upper surface (362) is, the less resistance upper surface(362) will provide to left (counterclockwise) rotation of knob (228)from the home position. The angle of upper surface (362) in the presentexample is selected to provide a substantially equal resistance force toinitial rotation of knob (228) from the home position in the left(counterclockwise) direction as the resistance force encountered withinitial rotation of knob (228) from the home position in the right(clockwise) direction. Other suitable configurations for protrusion(360) will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

It should also be understood that the symmetry/asymmetry of surfaces(362, 364) may have a negligible effect on rotation of knob (228) onceknob (228) has substantially left the home position (e.g., whenprotrusion (360) is completely displaced from recess (340)). Detent arm(350) and detent pad (352) do not substantially interfere with the freerotation of knob (228); and that the friction between detent pad (352)and cylindraceous portions (320 a, 320 b) will be negligible when detentpad (352) is disengaged from recess (340). It should also be understoodthat when detent pad (352) snaps into engagement with recess (340)(e.g., upon straightening of the articulation section), this snappingengagement may heard by the surgeon and/or be felt by the surgeonthrough handpiece (220). Other suitable ways of providing audible and/ortactile feedback to indicate one or more articulation states will beapparent to those of ordinary skill in the art in view of the teachingsherein.

It should be understood that the above described articulation controlcomponents of instrument (200) may operate in a manner that issubstantially similar to the manner that is shown in FIGS. 17A-17C anddescribed above. Alternatively, the above described articulation controlcomponents of instrument (200) may operate in some other fashion. Itshould also be understood that, as described above with respect toinstrument (100), manufacturing inconsistencies may be addressed at thedistal ends of bands (260, 270). For instance, before the distal ends ofbands (260, 270) are secured to the proximal portion of the endeffector, the articulation section may be held in a straightconfiguration and bands (260, 270) may be pulled distally to remove anyslack in bands (260, 270). With bands (260, 270) both being in tension,bands (260, 270) may then be welded or otherwise secured to the proximalportion of the end effector. As previously noted, this form ofcalibration is not limited to instruments (100, 200), such that thisform of calibration may be readily applied to various other instrumentsdescribed herein, among others. Other suitable structures and methodsfor calibration will be apparent to those of ordinary skill in the artin view of the teachings herein.

IV. Exemplary Shaft Rotation Control Configurations

As noted above, instrument (10, 100) may provide rotation of an endeffector (40, 140) and/or shaft (30, 130) via a knob (34, 134).Likewise, instrument (200) may provide rotation of its end effectorand/or shaft (230), relative to handpiece (220), via a knob (234). Suchrotation may provide rotation of the end effector and shaft (230)unitarily. In some other versions, knob (234) is operable to rotate endeffector (240) without rotating any portion of shaft (230) that isproximal of the articulation section. As another merely illustrativeexample, electrosurgical instrument (200) may include one rotationcontrol that provides rotatability of shaft (230) and the end effectoras a single unit; and another rotation control that providesrotatability of the end effector without rotating any portion of shaft(230) that is proximal of the articulation section. Other suitablerotation schemes will be apparent to those of ordinary skill in the artin view of the teachings herein.

In some instances, it may be desirable to selectively lock therotational position of shaft (30, 130, 230) and/or the end effector (40,140). By way of example only, instrument (10, 100, 200) may include apivoting member, sliding member, or some other type of manually movablemember that selectively engages a feature that is integral with knob(34, 134, 234) and thereby positively secures the rotational position ofknob (34, 134, 234) relative to handpiece (20, 120, 220). Such arotational locking feature may be controlled manually from handpiece(20, 120, 220) at any time during use of instrument (10, 100, 200).Various suitable forms that such a manual rotational locking feature maytake will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

As another merely illustrative variation, instrument (10, 100, 200) maybe configured to selectively lock the rotational position of shaft (30,130, 230) and/or end effector (40, 140) whenever the articulationsection (36, 136) is in an articulated configuration. In other words,such versions of instrument (10, 100, 200) may be configured to permitrotation of shaft (30, 130, 230) and/or end effector (40, 140) only whenthe articulation section (36, 136) is in a straight configuration. Thisselective locking of rotation may be automatically based on thearticulation state of the articulation section (36, 136), such that theuser need not provide a separate rotation lock input.

FIGS. 26-28 show an example of features that may be used to provideautomatic locking of rotation of shaft (30, 130, 230) and/or the endeffector (40, 140) when the articulation section (36, 136) is in a bentconfiguration. These features nevertheless permit rotation of shaft (30,130, 230) and/or the end effector (40, 140) when the articulationsection (36, 136) is in a straight configuration. In particular, FIG. 26shows an exemplary alternative rivet member (491). This rivet member(491) includes a series of distally extending protrusions (495)angularly arrayed on the distal face (493) of rivet member (491).Protrusions (495) are spaced such that a plurality of gaps (497) arepositioned between protrusions (495). FIG. 27 shows rivet member (491)positioned in first lead screw (283), though it should be understoodthat first lead screw (183) may also be fitted with a feature similar torivet member (491). FIG. 27 also shows second lead screw (284) fittedwith a second rivet member (492), which is substantially identical tofirst rivet member (491). In this example, drive member (272) includes adistal lateral protrusion (273) that is spaced distally from rivetmember (491) when the articulation section is in a straightconfiguration. Similarly, a distal lateral protrusion (263) of drivemember (262) is spaced distally from rivet member (492). This spacingpermits shaft (230), the end effector, and rotationally linkedcomponents including drive members (272, 273) to rotate relative torivet members (491, 492) and relative to housing (221) when knob (234)is rotated.

When knob (228) is rotated in a first rotational direction bend thearticulation section in a first direction, first lead screw (283)advances distally while second lead screw (284) moves proximally. Thedistal movement of first lead screw (283) results in entry of lateralprotrusion (273) into one of the gaps (497) of rivet member (491). Withlateral protrusion (273) so positioned, protrusions (495) of rivetmember (491) substantially secure the rotational position of lateralprotrusion (273). Since the rotational positions of rivet member (491)and first lead screw (283) are fixed relative to housing (221) via pins(223), and since the rotational position of drive member (272) is fixedrelative to shaft (230) and the end effector, the positioning of lateralprotrusion (273) between protrusions (495) will secure the rotationalposition of shaft (230) and the end effector relative to housing (221).Rivet member (491) thus prevents rotation of shaft (230) and/or the endeffector when the articulation section is bent in a first direction.When the articulation section is later straightened by rotating knob(228) in a second rotational direction, lateral protrusion (273)eventually exits gap (497) and is spaced away from rivet member (491),such that rivet member (491) no longer prevents shaft (230) and/or theend effector from rotating relative to housing (221).

Similarly, when knob (228) is rotated in a second direction to bend thearticulation section in a second direction, second lead screw (284)advances distally while first lead screw (283) moves proximally. Thedistal movement of second lead screw (284) results in engagement betweensecond rivet member (492) and lateral protrusion (263) in a mannersimilar to that described above for first rivet member (491) and lateralprotrusion (273). Rivet member (492) thus prevents rotation of shaft(230) and/or the end effector when the articulation section is bent in asecond direction. When the articulation section is later straightened byrotating knob (228) in the first rotational direction, lateralprotrusion (263) eventually disengages rivet member (492), such thatrivet member (492) no longer prevents shaft (230) and/or the endeffector from rotating relative to housing (221). In some versions,rivet members (491, 492) include angularly arrayed recesses in place ofprotrusions (495), such that rivet members (491, 492) lock rotation ofshaft (230) and/or the end effector when a corresponding lateralprotrusion (273, 263) is disposed in one of the recesses. In some suchversions, lateral protrusions (263, 273) include proximally extendingportions to enter the recesses of rivet members (491, 492). Othersuitable ways in which rotation of shaft (30, 130, 230) and/or endeffector (40, 140) may be automatically locked based on the articulationstate of the articulation section (36, 136) will be apparent to those ofordinary skill in the art in view of the teachings herein.

As yet another merely illustrative variation, instrument (10, 100, 200)may be configured to provide relatively low resistance to rotation ofshaft (30, 130, 230) and/or end effector (40, 140) when the articulationsection (36, 136) is in a straight configuration; yet provide relativelyhigh resistance to rotation of shaft (30, 130, 230) and/or end effector(40, 140) when the articulation section (36, 136) is in an articulatedconfiguration. Some such versions may still permit rotation of shaft(30, 130, 230) and/or end effector (40, 140) when the articulationsection (36, 136) is in an articulated configuration, albeit at a higherresistance than that encountered when the articulation section (36, 136)is in a straight configuration. FIG. 28 shows one merely illustrativeexample of a feature that may be used to provide varied resistance torotation of shaft (30, 130, 230) and/or end effector (40, 140). Inparticular, FIG. 28 shows a friction ring (700) positioned in a recess(533) of housing (521). Friction ring (700) is positioned to contact aflange (633) that is unitary with shaft (630). It should be understoodthat housing (521) may be viewed as being otherwise analogous to housing(121, 221); and shaft (630) analogous to shaft (130, 230), etc.

Friction ring (700) may comprise any suitable material, including butnot limited to rubber, silicone, isoprene, some other type ofelastomeric material, etc. In the present example, friction ring (700)is compressed between flange (633) and housing (521) by approximately0.005 inches when the articulation section of shaft (630) is in asubstantially straight configuration. This may provide some relativelylow resistance to rotation of shaft (630) relative to housing (521).When the articulation section of shaft is bent to an articulatedconfiguration (e.g., using one of the articulation assemblies describedabove, etc.), this may produce backloading on shaft (630), such thatshaft (630) is urged proximally even by a slight degree. This mayfurther compress friction ring (700), which may in turn increase thefriction between friction ring (700) and flange (633). This increasedfriction may thereby provide additional resistance to rotation of shaft(630) when the articulation section is bent to an articulatedconfiguration.

FIGS. 29-30B show yet another merely illustrative example of featuresthat may be used to provide varied resistance to rotation of shaft (30,130, 230) and/or end effector (40, 140). In particular, FIG. 29 shows abrake disc (800) that includes an integral elastomeric brake pad (810).In the present example, disc (800) is positioned between lead screws(283, 284), though it should be understood that disc (800) mayalternatively be positioned distal to lead screw (283) or proximal tolead screw (284). It should also be understood that lead screw (284) isomitted from FIG. 29 for clarity. Cylindraceous portion (320) of knob(228) Includes an inwardly extending annular flange (321), which isreceived in an annular recess (802) formed in the outer perimeter ofdisc (800). This relationship between flange (321) and recess (802)longitudinally restrains disc (800) within cylindraceous portion (320)while still permitting knob (228) to rotate relative to disc (800). Pins(223) pass through disc (800) and prevent disc (800) from rotating.

As best seen in FIGS. 30A-30B, pad (810) has a non-circular profile,with an outer profile resembling that of a nautilus shell. As also seenin FIGS. 30A-30B, cylindraceous portion (320) includes in inwardlyextending cam fin (820) that progressively engages the outer perimeterof pad (810) when knob (228) (and, hence, cylindraceous portion (320))is rotated. In particular, FIG. 30A shows the components positioned whenknob (228) is at the home position, with the articulation section ofshaft (230) in a substantially straight configuration. At this stage,cam fin (820) is spaced away from pad (810). FIG. 30B shows thecomponents positioned when knob (228) (and, hence, cylindraceous portion(320)) has been rotated to the left (counterclockwise) to bend thearticulation section in a first direction. At this stage, cam fin (820)bears into pad (810). It should be understood that cam fin (820) willbegin bearing into pad (810) during part of the transition from thestage shown in FIG. 30A to the stage shown in FIG. 30B, and the degreeof this bearing into pad (810) by cam fin (820) will progressivelyincrease as knob (228) continues to rotate. As can also be seen in FIG.30B, the bearing of cam fin (820) into the outer perimeter of pad (810)causes pad (810) to deform and thereby cause the inner diameter of pad(810) to bear against cutting member driver tube (238). This bearing ofpad (810) against cutting member driver tube (238) provides frictionalresistance against rotation of cutting member driver tube (238), andhence, against rotation of shaft (230). Thus, rotation of knob (228) toarticulate the articulation section of shaft (230) will substantiallyprevent rotation of shaft (230) relative to handpiece (220).Furthermore, the resistance to rotation of shaft (230) relative tohandpiece (220) will increase in proportion to the articulation angledefined by the articulation section of shaft (230).

While the example shown in FIGS. 29-30B and described above providesincreasing resistance to rotation of shaft (230) relative to handpiece(220) in response to left (counterclockwise) rotation of knob (228), itshould be understood that similar components may be used to provideincreasing resistance to rotation of shaft (230) relative to handpiece(220) in response to right (clockwise) rotation of knob (228). Forinstance, such components may include a brake pad and cam fin that areessentially a mirror image of pad (810) and fin (820) shown in FIGS.29-30B. In some versions, pad (810) is provided on the proximal face ofdisc (800) while a mirror image of pad (810) is provided on the distalface of disc (800). In some other versions, a mirror image of pad (810)is provided on a separate disc. Other suitable ways in which rotation ofshaft (30, 130, 230) and/or end effector (40, 140) may be selectivelyresisted based on the articulation state of the articulation section(36, 136) will be apparent to those of ordinary skill in the art in viewof the teachings herein.

In versions of instrument (10, 100, 200) that provide rotation of ashaft (30, 130, 230) and/or the end effector (40, 140), instrument (10,100, 200) may provide some form of user feedback relating to therotational position of shaft (230) and/or the end effector. Forinstance, rotation knob (34, 134, 234) and/or shaft (30, 130, 230)and/or the end effector (40, 140) may include one or more markingsfacilitating visual identification of the rotational position. A usermay correlate a marking on a rotation knob (34, 134, 234) with acorresponding marking on shaft (30, 130, 230) and/or the end effector(40, 140) to better understand the orientation of such components withrespect to the patient and instrument (10, 100, 200). Providing amarking on the articulation section (36, 136), on the end effector (40,140), and/or on some other portion of instrument (10, 100, 200) thatwill be positioned within the patient may facilitate viewing of themarking within the image provided by an endoscopic camera, such that thesurgeon need not look away from the surgical field presented on a screencoupled with the endoscopic camera in order to determine the rotationalorientation of the end effector. In addition to or as an alternative tovisual markings, instrument (10, 100, 200) may include a detent featureand/or some other feature(s) that are operable to provide audible and/ortactile feedback to indicate rotational orientation of the end effector.Various other suitable ways in which rotation of the end effector andassociated feedback may be provided will be apparent to those ofordinary skill in the art in view of the teachings herein. Of course,some versions of instrument (10, 100, 200) may lack rotatability of theend effector.

V. Miscellaneous

It should be understood that any of the versions of electrosurgicalinstrument (10) described herein may include various other features inaddition to or in lieu of those described above. By way of example only,any of the devices herein may also include one or more of the variousfeatures disclosed in U.S. Pub. No. 2012/0078243, entitled “ControlFeatures for Articulating Surgical Device,” published Mar. 29, 2012, thedisclosure of which is incorporated by reference herein; U.S. Pub. No.2012/0078244, entitled “Control Features for Articulating SurgicalDevice,” published Mar. 29, 2012, the disclosure of which isincorporated by reference herein; U.S. Pub. No. 2012/0078247, entitled“Articulation Joint Features for Articulating Surgical Device,”published Mar. 29, 2012, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2012/0078248, entitled “ArticulationJoint Features for Articulating Surgical Device,” published Mar. 29,2012, the disclosure of which is incorporated by reference herein;and/or U.S. Patent App. No. [ATTORNEY DOCKET NO. END6888USCIP1.0595865],entitled “Surgical Instrument with Multi-Phase Trigger Bias,” filed oneven date herewith, the disclosure of which is incorporated by referenceherein.

It should also be understood that any of the devices described hereinmay be modified to include a motor or other electrically powered deviceto drive an otherwise manually moved component. Various examples of suchmodifications are described in U.S. Pub. No. 2012/0116379, entitled“Motor Driven Electrosurgical Device with Mechanical and ElectricalFeedback,” published May 10, 2012, the disclosure of which isincorporated by reference herein. Various other suitable ways in which amotor or other electrically powered device may be incorporated into anyof the devices herein will be apparent to those of ordinary skill in theart in view of the teachings herein.

It should also be understood that any of the devices described hereinmay be modified to contain most, if not all, of the required componentswithin the medical device itself. More specifically, the devicesdescribed herein may be adapted to use an internal or attachable powersource instead of requiring the device to be plugged into an externalpower source by a cable. Various examples of how medical devices may beadapted to include a portable power source are disclosed in U.S.Provisional Application Ser. No. 61/410,603, filed Nov. 5, 2010,entitled “Energy-Based Surgical Instruments,” the disclosure of which isincorporated by reference herein. Various other suitable ways in which apower source may be incorporated into any of the devices herein will beapparent to those of ordinary skill in the art in view of the teachingsherein.

While the examples herein are described mainly in the context ofelectrosurgical instruments, it should be understood that the teachingsherein may be readily applied to a variety of other types of medicalinstruments. By way of example only, the teachings herein may be readilyapplied to tissue graspers, tissue retrieval pouch deployinginstruments, surgical staplers, ultrasonic surgical instruments, etc. Itshould also be understood that the teachings herein may be readilyapplied to any of the instruments described in any of the referencescited herein, such that the teachings herein may be readily combinedwith the teachings of any of the references cited herein in numerousways. Other types of instruments into which the teachings herein may beincorporated will be apparent to those of ordinary skill in the art.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Embodiments of the present invention have application in conventionalendoscopic and open surgical instrumentation as well as application inrobotic-assisted surgery. For instance, those of ordinary skill in theart will recognize that various teaching herein may be readily combinedwith various teachings of U.S. Pat. No. 6,783,524, entitled “RoboticSurgical Tool with Ultrasound Cauterizing and Cutting Instrument,”published Aug. 31, 2004, the disclosure of which is incorporated byreference herein.

Embodiments of the devices disclosed herein can be designed to bedisposed of after a single use, or they can be designed to be usedmultiple times. Embodiments may, in either or both cases, bereconditioned for reuse after at least one use. Reconditioning mayinclude any combination of the steps of disassembly of the device,followed by cleaning or replacement of particular pieces, and subsequentreassembly. In particular, embodiments of the device may bedisassembled, and any number of the particular pieces or parts of thedevice may be selectively replaced or removed in any combination. Uponcleaning and/or replacement of particular parts, embodiments of thedevice may be reassembled for subsequent use either at a reconditioningfacility, or by a surgical team immediately prior to a surgicalprocedure. Those skilled in the art will appreciate that reconditioningof a device may utilize a variety of techniques for disassembly,cleaning/replacement, and reassembly. Use of such techniques, and theresulting reconditioned device, are all within the scope of the presentapplication.

By way of example only, embodiments described herein may be processedbefore surgery. First, a new or used instrument may be obtained and ifnecessary cleaned. The instrument may then be sterilized. In onesterilization technique, the instrument is placed in a closed and sealedcontainer, such as a plastic or TYVEK bag. The container and instrumentmay then be placed in a field of radiation that can penetrate thecontainer, such as gamma radiation, x-rays, or high-energy electrons.The radiation may kill bacteria on the instrument and in the container.The sterilized instrument may then be stored in the sterile container.The sealed container may keep the instrument sterile until it is openedin a medical facility. A device may also be sterilized using any othertechnique known in the art, including but not limited to beta or gammaradiation, ethylene oxide, or steam.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

1-20. (canceled)
 21. A surgical instrument, comprising: (a) a shaftassembly defining a longitudinal axis, (b) an end effector; (c) anarticulation section extending between the shaft assembly and the endeffector, wherein the articulation section is configured to deflect theend effector relative to the longitudinal axis of the shaft assembly;and (d) an articulation drive assembly configured to drive thearticulation section, wherein the articulation drive assembly comprises:(i) a rotary member configured to rotate relative to the shaft assemblyabout an axis of rotation that is parallel with the longitudinal axis,(ii) a first lead member configured to translate in a first direction inresponse to rotation of the rotary member relative to the shaftassembly, and (iii) a second lead member configured to translate in asecond direction in response to rotation of the rotary member relativeto the shaft assembly, wherein translation of the of the first leadmember in the first direction and translation of the second lead memberin the second direction are configured to drive the articulation sectionto deflect the end effector relative to the longitudinal axis.
 22. Thesurgical instrument of claim 21, further comprising a handle assembly.23. The surgical instrument of claim 22, wherein the rotary member isrotatably coupled with the handle assembly.
 24. The surgical instrumentof claim 21, wherein the axis of rotation and the longitudinal axis arecoaxial.
 25. The surgical instrument of claim 21, wherein the rotarymember comprises two separate pieces configured to couple together. 26.The surgical instrument of claim 21, wherein the rotary member defines achamber housing the first lead member and the second lead member. 27.The surgical instrument of claim 21, wherein the articulation driveassembly further comprises a first articulation band coupled with thefirst lead member, and a second articulation band coupled with thesecond lead member.
 28. The surgical instrument of claim 27, wherein thefirst articulation band and the second articulation band extend alongthe shaft assembly and are coupled with the articulation section. 29.The surgical instrument of claim 21, wherein the rotary member defines afirst internal threading and a second internal threading.
 30. Thesurgical instrument of claim 29, wherein the first internal threadingand the second internal threading comprising opposing pitch angles. 31.The surgical instrument of claim 30, wherein the first lead membercomprises a first external threading configured to mesh with the firstinternal threading of the rotary member.
 32. The surgical instrument ofclaim 31, wherein the second lead member comprises a second externalthreading configured to mesh with the second internal threading of therotary member.
 33. The surgical instrument of claim 21, wherein thefirst lead member comprises a first rivet, wherein the second leadmember comprises a second rivet.
 34. The surgical instrument of claim21, wherein the end effector is configured to provide bipolar RF energy.35. The surgical instrument of claim 21, wherein the end effectorcomprises a jaw.
 36. The surgical instrument of claim 21, wherein theshaft assembly comprises a separator.
 37. The surgical instrument ofclaim 36, wherein the separator defines three lumens.
 38. A surgicalinstrument, comprising: (a) a shaft assembly defining a longitudinalaxis, (b) an end effector; (c) an articulation section extending betweenthe shaft assembly and the end effector, wherein the articulationsection is configured to deflect the end effector relative to thelongitudinal axis of the shaft assembly; and (d) an articulation driveassembly configured to drive the articulation section, wherein thearticulation drive assembly comprises: (i) a rotary member configured torotate relative to the shaft assembly to drive the articulation sectionto deflect the end effector relative to the longitudinal axis of theshaft assembly, and (ii) a tactile feedback assembly configured toprovide tactile feedback when the rotary member is in a positionassociated with the end effector in a straight configuration relative tothe longitudinal axis.
 39. The surgical instrument of claim 38, whereinthe tactile feedback assembly comprises a tactile pad.
 40. A surgicalinstrument, comprising: (a) a shaft assembly defining a longitudinalaxis, wherein the shaft assembly is configured to rotate about thelongitudinal axis, (b) an end effector; (c) an articulation sectionextending between the shaft assembly and the end effector, wherein thearticulation section is configured to deflect the end effector relativeto the longitudinal axis of the shaft assembly; (d) an articulationdrive assembly configured to drive the articulation section; and (e) arotary braking feature configured to inhibit rotation of the shaftassembly about the longitudinal axis when the end effector is deflectedrelative to the longitudinal axis of the shaft assembly.